Mustafa al-Gharib served with an al-Qaeda-linked group. Born Damian Clairmont, he left Calgary to fight in Syria in Nov. 2012

The latest details of a Canadian citizen executed during Syrian rebel infighting have once again pushed to the forefront the issue of national security, and the question of why so many Canadians are joining radical extremist groups.

That question circles the recent death of Mustafa al-Gharib, 22, born in Nova Scotia as Damian Clairmont before converting to Islam at the age of 17.

Reports suggest al-Gharib joined a rebel group opposing the reign of President Bashar Assad after leaving Canada in 2012. He was reportedly killed by the Free Syrian Army during infighting among rebel groups earlier this week.

Al-Gharib was dropped out of high school and attempted suicide before converting to Islam. In a 2013 interview with the National Post, he said it was “between me and God” as to why he had decided to travel to Syria, where rebel forces wage war against the despotic Assad regime, and also where al-Qaeda-linked terror groups are believe to recruit and train fighters.

The Department of Foreign Affairs has not confirmed al-Gharib death, but Minister John Baird told the Canadian Press they were aware of the reports, and that he is likely one of many Canadians fighting in Syria.

"I haven't got specific facts, (but) it won't come as a surprise to us that there is probably more than one Canadian that is fighting with the opposition," he told the news agency.

Indeed, this is by no stretch the first time a Canadian citizen has been captured or killed fighting with extremist groups overseas.

In September, there were reports that a 24-year-old Ontario man was among a group of gunmen who stormed a Nairobi shopping centre, killing more than 60 people. Ali Mohamed Dirie, a convicted participant in the "Toronto 18" terror plot, was reportedly shot and killed the same month while fighting in Syria.

Xristos Katsiroubas and Ali Medlej, two young men from London, Ont., were also killed late last year after fighting with an al-Qaeda-linked militant group during an attack on an Algerian gas plant.

New information about Katsiroubas' role in the attack have recently come to light, including information that suggests he helped link hostages to explosive devices and fired a machine gun at a military helicopter.

It has been estimated by security officials that at least 100 young Canadians left to join fighting in Syria last year – which no doubt played a factor in the federal government passing the Combating Terrorism Act in April. That act makes it illegal for a Canadian to leave, or attempt to leave, the country to participate in terrorist activities.

Interestingly, al-Gharib's grandfather has suggested that Canada's spy agency was to blame for his grandson's death because they failed to stop him from travelling overseas. Gerry Boudreau told CBC News that CSIS had been surveilling al-Gharib but still allowed him to travel to Syria in 2012.

"I'm just really upset at the cavalier attitude that the Canadian government has taken to the recruiting of young people in Canada," he told the network.

If nothing else, that seems to be a vote of confidence for Canada's Combating Terrorism Act. While it has been challenged as unconstitutional, it is at least possible al-Gharib would have been stopped at the border had the law been in place when he left for Syria.

Then again, there is no way to be sure it would have stopped any Canadian aiming to fight with extremist groups overseas, or whether it really can stop the next one.